Perform swaps

This guide will walk you through how to perform swaps with Portal's iOS SDK.

Please contact sales for additional pricing information on using the Swaps integrations at [e-mail]

The PortalSwaps class allows you to easily extend your existing Portal instance with swaps functionality.

Initializing Swaps

In order to initialize the Swaps class you need an existing Portal instance and a Swaps API Key. If you have not received a Swaps API Key, please contact support at [e-mail].

var swaps = PortalSwaps(
    apiKey: "SWAPS-API-KEY", 
    portal: portal
)

Fetching a list of Sources

The getSources() function returns a dictionary containing valid, swappable token sources that can be used with your Portal MPC Wallet. The existing Portal instance that was provided at initialization is used to scope the request to the current chain.

In order to retrieve this list, you can use the following code.

swaps.getSources() { result in
    var sources = result.data
}

The returned list

The dictionary returned by the getSources() function is a set of key/value pairs where the key is the name of the token and the value is the token address for that token.

Fetching a swap Quote

The getQuote() function returns a Quote object for a given set of arguments.

QuoteArgs

The minimum requirements for a valid set of Quote arguments are a buyToken, a sellToken, and either a buyAmount or a sellAmount.

An example of a valid QuoteArgs object would look something like this.

var quoteArgs = QuoteArgs(
    buyToken: "UNI", // You can also use the token address instead, e.g. "0x1f9840a85d5af5bf1d1762f925bdaddc4201f984"
    sellToken: "ETH",
    sellAmount: "10000", // Base units of the token
)

Using your QuoteArgs

Once you have a valid QuoteArgs object, you can call the getQuote() function.

swaps.getQuote(args: quoteArgs) { result in
    var quote = result.data
}

The Quote object

The Quote object includes two properties:

• allowanceTarget The address requiring allowances to complete the Swap

• cost The total cost (gas fees) of the swap transaction

• transaction The transaction to perform the swap

Executing a Swap

If you're selling ERC20 tokens, you'll need to utilize the allowanceTarget to give the associated contract permissions to access a given amount of the token you're selling. This requires a token allowance of at least what you're selling. If you're selling ETH, this step is not necessary.

When you're ready to execute a swap, you can use the Provider on your existing Portal instance to sign the transaction and make a request to chain.

let requestResponse = try await portal.request(
  chainId, // CAIP-2 format (e.g. "eip155:11155111" for Ethereum Sepolia)
  withMethod: .eth_sendTransaction,
  andParams: [transaction]
)